Just my opinion, but I've stayed at the Conrad Tulum and WA Los Cabos, and in no way feel they are in the same league. Conrad Tulum is a nice property, with good food and an excellent breakfast offering. But the service level and in room experience are worlds apart. Tulum has that beautiful water and that can't be missed. Great rates can be found and stacked using Amex's FHR offering. Sharing my review from about six months ago: https://www.flyertalk.com/forum/34541829-post94.html